Biologists have created more than a hundred chimeras of monkeys and humans in the laboratory
Researchers from the United States and China have grown monkey embryos containing human cells in the laboratory. The head of the scientific experiment was Juan Carlos Ispisua Belmonte of the Salk Institute in the United States, who helped create the first human-pig hybrid in 2017, Cell reports.
In the course of previous experiments, an attempt was also made to create a “chimera” of man and sheep. But in both cases, the number of successfully engrafted human cells was very low. This indicated a certain incompatibility of tissues of different types at the molecular level.
The authors of the new study decided to use the embryos of the macaque (Macaca fascicularis), since they are, albeit distant, but still related to humans. Each of the blastocysts was injected with 25 human expanded pluripotent stem cells. These cells are capable of forming both the embryo itself and the tissues surrounding it.
The researchers were able to see that human cells integrated successfully into 132 macaque embryos. After 10 days, 103 embryos were alive and successfully developed. But after this period, the survival rate began to decline, and by the 19th day only three chimeras remained alive. They were subsequently destroyed.
The experiment turned out to be more successful than the creation of a hybrid of a human and a pig in 2017. In addition, genetic sequencing of blastocyst cells has indicated new pathways for cell communication within hybrids – this is useful for future studies of this kind.
But experiments on the creation of human “chimeras” invariably cause heated debate in the scientific community. Many experts are convinced that they are highly unethical. The authors of the studies argue that the data they obtain are important for the development of biochemistry. By observing hybrid embryos, you can better understand the earliest stages of the human body. In addition, this technology may allow in the future to grow organs for transplantation, rather than waiting for a suitable donor.
Earlier it was reported that American scientists have grown human muscles in a pig embryo. The created embryos developed within 27 days.
